$ git clone -n https://src.fedoraproject.org/rpms/rubygem-unicode.git /var/lib/mock/f45-build-35390-695/root/chroot_tmpdir/scmroot/rubygem-unicode
Cloning into '/var/lib/mock/f45-build-35390-695/root/chroot_tmpdir/scmroot/rubygem-unicode'...
$ git fetch origin 7af998b5fb0bbb4abe2dcff18de6cd1156f2987a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-unicode
 * [new ref]         7af998b5fb0bbb4abe2dcff18de6cd1156f2987a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7af998b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild